1. Structural Biology and Molecular Biophysics
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A processive rotary mechanism couples substrate unfolding and proteolysis in the ClpXP degradation machinery

  1. Zev A Ripstein  Is a corresponding author
  2. Siavash Vahidi  Is a corresponding author
  3. Walid A Houry
  4. John L Rubinstein  Is a corresponding author
  5. Lewis E Kay  Is a corresponding author
  1. University of Toronto, Canada
Research Article
  • Cited 30
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Cite this article as: eLife 2020;9:e52158 doi: 10.7554/eLife.52158

Abstract

The ClpXP degradation machine consists of a hexameric AAA+ unfoldase (ClpX) and a pair of heptameric serine protease rings (ClpP) that unfold, translocate, and subsequently degrade client proteins. ClpXP is an important target for drug development against infectious diseases. Although structures are available for isolated ClpX and ClpP rings, it remains unknown how symmetry mismatched ClpX and ClpP work in tandem for processive substrate translocation into the ClpP proteolytic chamber. Here we present cryo-EM structures of the substrate-bound ClpXP complex from Neisseria meningitidis at 2.3 to 3.3 Å resolution. The structures allow development of a model in which the sequential hydrolysis of ATP is coupled to motions of ClpX loops that lead to directional substrate translocation and ClpX rotation relative to ClpP. Our data add to the growing body of evidence that AAA+ molecular machines generate translocating forces by a common mechanism.

Article and author information

Author details

  1. Zev A Ripstein

    Department of Biochemistry, University of Toronto, Toronto, Canada
    For correspondence
    zevripstein@gmail.com
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3601-0596
  2. Siavash Vahidi

    Department of Biochemistry, University of Toronto, Toronto, Canada
    For correspondence
    siavashvahidi@gmail.com
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8637-3710
  3. Walid A Houry

    Department of Biochemistry, University of Toronto, Toronto, Canada
    Competing interests
    No competing interests declared.
  4. John L Rubinstein

    Department of Biochemistry, University of Toronto, Toronto, Canada
    For correspondence
    john.rubinstein@sickkids.ca
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0566-2209
  5. Lewis E Kay

    Department of Biochemistry, University of Toronto, Toronto, Canada
    For correspondence
    kay@pound.med.utoronto.ca
    Competing interests
    Lewis E Kay, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4054-4083

Funding

Canadian Institutes of Health Research (FDN-503573)

  • Lewis E Kay

Canadian Institutes of Health Research (PJT-162186)

  • John L Rubinstein

Canadian Institutes of Health Research (PJT-148564)

  • Walid A Houry

Canadian Institutes of Health Research

  • Zev A Ripstein

Canadian Institutes of Health Research

  • Siavash Vahidi

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Axel T Brunger, Stanford University, United States

Publication history

  1. Received: September 24, 2019
  2. Accepted: January 8, 2020
  3. Accepted Manuscript published: January 9, 2020 (version 1)
  4. Version of Record published: April 1, 2020 (version 2)

Copyright

© 2020, Ripstein et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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